Highly improved transportation system

ABSTRACT

The disclosure is of a transportation system which includes an elongated guidebeam having three spaced apart running surfaces. Two of the running surfaces as substantially vertical to accommodate wheels rotating about vertical axles and the third running surface is substantially horizontal to accomodate wheels rotating on horizontal axles. Wheels which rotate on a normally vertical axle and wheels which rotate on a normally horizontal axle are connected to a rack which is adapted to move along the running surfaces of the guidebeam. The wheels connect the rack on the side of the guidebeam in cantilever fashion. Connecting switch sections are provided at desired locations on the elongated guidebeam to connect two or more guidebeams. The switch sections have no moving parts and cooperate with wheels of the rack which are movable on the guidebeam by self-contained means carried on the rack in a direction normal to the direction of travel of the rack to provide for high speed switching of the rack between an upline guidebeam and one of two or more spaced apart downline guidebeams and between two or more spaced apart upline guidebeams and a single downline guidebeam.

United States Patent 1191 Jacobs, Jr. et al.

[451 Nov. 5, 1974 1 HIGHLY IMPROVED TRANSPORTATION SYSTEM [76] Inventors: Justin M. Jacobs, Jr., 1245 Jones St., San Francisco, Calif. 94109; Neil S. Stafford, Rt. 3, Box 355, San Jose, Calif. 95121 [22] Filed: Aug. 13, 1973 [21] Appl. No.: 388,215

Related US. Application Data [62] Division of Ser. No. 212,906, Dec. 28, 1971, Patv No.

[52] US. Cl 105/147, 104/105, 104/130, 104/121 [51] rm. Cl B6lb 13/04 [58] Field of Search 104/88, 89, 96, 105, 121, 104/130, 119, 131, 118; 105/215 R, 141, IDS/144,146,147

[56] V References Cited UNITED STATES PATENTS 3,194,179 7/1965 Scherer 104/121 3,777,669 12/1973 Lott 104/130 Primary Examiner-M. Henson Wood, Jr. Assistant Examiner-D. W. Keen Attorney, Agent, or FirmEdward J. Keeling [57] ABSTRACT The disclosure is of a transportation system which includes an elongated guidebeam having three spaced apart running surfaces. Two of the running surfaces as substantially vertical to accommodate wheels rotating about vertical axles and the third running surface is substantially horizontal to accomodate wheels rotating on horizontal axles. Wheels which rotate on a normally vertical axle and wheels which rotate on 21 normally horizontal axle are connected to a rack which is adapted to move along the running surfaces of the guidebeam. The wheels connect the rack on the side of the guidebeam in cantilever fashion. Connecting switch sections are provided at desired locations on the elongated guidebeam to connect two or more guidebeams. The switch sections haye no moving parts and cooperate with wheels of the rack which are mov able on the guidebeam by self-contained means carried on the rack in a direction normal to the direction of travel of the rack to provide for high speed switching of the rack between an upline guidebeam and one of two or more spaced apart downline guidebeams and between two or more spaced apart upline guidebeams and a single downline guidebeam.

12 Claims, 46 Drawing Figures PAIENIEDNUY 519m 3.845723 sum 10$ 8 PATENTEDIIUY 51974 SHEH 8 BF 8 V OE MEmwuuv 5m. 3.8451723 sum so: a

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HIGHLY IMPROVED TRANSPORTATION SYSTEM This is a division of application Ser. No. 212,906, filed Dec. 28, 1971, now U.S. Pat. No. 3,760,740. RE- LATED APPLICATIONS This application is related to our application Ser. No. 746884, filed July 23, 1968 for Transportation System, and now U.S. Pat. No. 3,606,839 and is a continuation in part to our pending application, Ser. No. 861,843, filed Sept. 29, 1969 for Improved Transportation System, now U.S. Pat. No. 3,659,529. The disclosures of these applications are herein incorporated by reference.

FIELD OF THE INVENTION This invention relates to a transportation system which includes an elongated guidebeam having running surfaces for cantilevering a rack on, and more specifically the invention deals with a transportation system having connecting switch sections for switching a rack between upline and downline guidebeams without the necessity of moving parts in the connecting switch sectrons.

BACKGROUND OF THE INVENTION A particular problem which has plagued most fixed rail guidebeam transportation systems has occured in switching the moving member or rack from one fixed rail section to a second fixed rail section which is either horizontally or vertically diverging from the main section. For example this problem was exemplified by conventional railroad transportation systems wherein it has been necessary to provide a moving switch section between two diverging portions of the track to allow switching of the train from one rail section to a second diverging rail section. Even a more serious problem has been encountered in monorail and cantilevered systems where there were no satisfactory switching methods.

In the first above mentioned related applications, Ser. No. 746.884, and now U.S. Pat. No. 3,606,839, we disclosed a method of vertically switching a cantilevered rack from an upline guidebeam to a downline guidebeam utilizing a moving section positioned pivotally on an intermediate connecting guidebeam switch section between two diverging guidebeams. It has been found that while movable switch sections of this nature are operative to provide for switching -a cantilevered rack, it is necessary, particularly in high density, high speed flow of racks in a cantilever system, that switching be accomplished without need for a movable section in the guidebeam switching section. This is particularly necessary where a computerized transportation system is desired which will allow for closely'spaced high speed travel ofa number of individual racks along a guidebeam system which may include many interchanges and switches. There will be many racks moving at very closely spaced intervals along the main guidebeam in such a system and it is often desirable to switch some of the racks to alternative guidebeams while a1- lowing other of the racks to pass through on the main guidebeam. The time lag required by the moving section of the heretofore disclosed connecting guidebeam switch section requires that a definite time interval and substantial leadway be maintained between the racks traveling on the main line guidebeams. Thus when utilizing a moving switch section the racks must maintain certain spaced intervals depending upon the speed and the time lag in the switch.

In our second above mentioned application Ser. No. 861,843, now U.S. Pat. No. 3,659,529, a unique transportation system was disclosed which has connecting swith sections having no moving parts. The switch sections cooperated with movable means, such as extendable and retractable wheels, of the rack to provide for selective high speed switching both in horizontal and vertical modes of the rack between an upline guidebeam and one or more spaced apart downline guidebeams and between two or more spaced apart upline guidebeams and a single downline guidebeam. The method and apparatus disclosed in our application Ser. No. 861,843 utilized an extendable and retractable support wheel rotating around a normally horizontal axle of a rack in cooperation with ramps or through paths in certain portions of a switch section to selectively elevate or not elevate guide wheels rotating aroundnormally vertical axles of a rack to selectively switch the rack on the guidebeams.

The present invention is directed to increasing the flexibility of a guidebeam transportation system by providing for selectively moving the guide wheels of a rack in a direction normal or transverse to the direction of travel of the rack without the use of a ramp in the guidebeam switch section. This mode of switching is particularly useful in horizontal switching of racks. The system of the present invention, of course, may be advantageously incorporated in a rack of our system disclosed in Ser. No. 861,843 now U.S. Pat. No. 3,659,529 and thus also utilize ramps of the guidebeam switch sections in addition to the self-contained vertical movement of the present invention to provide for multiple switching of racks at high speed on relatively short switch sections.

A BRIEF DESCRIPTION OF THE INVENTION The present invention includes an arrangement of guidebeams connected by specially devised nonmoving connecting guidebeam switch sections which cooperated with racks assembled in accordance with the invention to permit switching of the racks from the mainline guidebeam to a selected guidebeam of two or more spaced apart guidebeams. The racks utilize selfcontained means to selectively move guidewheels vertically on the guidebeam to determine the path of the rack through the switch section. The guidewheels are moved by self-contained equipment carried by the rack. Three embodiments of racks are disclosed in accordance with the invention. Connecting switch sections are described for each type of rack. The method and apparatus of the present invention are useful in the horizontal switching of cantilevered racks. The adaptability of switching of the present system is particularly useful when combined with our previous non-moving switch system in providing a complete network guidebeam system which is compatable with a wide range of topographical and station requirements.

The racks used in accordance with the present invention are cantilevered on a guidebeam by means of upper and lower guidewheels and a support wheel. The racks include a frame having the wheels mounted thereon. The wheels of the frame include two horizontally spaced apart upper guide wheels rotatably mounted on normally vertical axles. of the frame. Two horizontally spaced apart lower guidwheels are also rotatably mounted on normally vertical axles of the frame. At least a pair of spaced apart support wheels are rotatably mounted on horizontal axles of the frame. The support wheels are located between the upper guidewheels and lower guidewheels. Self-contained means are provided on the rack for moving the guidwheels in a direction normal to the direction of travel of the rack which, when the wheels are rotated, directs the rack along a selected path through the connecting switch section to a selected downline guidebeam.

OBJECT OF THE INVENTION BRIEF SUMMARY OF THE DRAWINGS FIG. I is a schematic perspective view and illustrates the modes of switching that are selectively accomplished in accordance with the present invention;

FIG. 2 is an elevation view and illustrates the preferred rack assembled in accordance with the invention;

FIG. 3 is a side elevation view and illustrates the preferred rack assembled in accordance with the invention;

FIG. 4 is a bottom view and illustrates the preferred rack assembled in accordance with the invention;

FIG. 5 is an elevation view and illustrates an alternative rack assembled in accordance with the invention;

FIG. 6 is a side elevation view and illustrates the alternative rack assembled in accordance with the invention with the guide wheels in a lower portion;

FIG. 7 is a side elevation view and illustrates the alternative rack assembled in accordance with the invention with the guidewheels in the upper position;

FIG. 8 is a bottom view and illustrates the alternative rack assembled in accordance with the invention;

FIG. 9 is a side elevation view of a connecting switch section providing horizontal switching in accordance with the invention;

FIGS. 9A-9E are sectional views taken as indicated from FIG. 9;

FIG. 10 is a partial top view of the connecting switch section of FIG. 9;

FIGS. 10A and 10B are sectional views taken as indicated from FIG. 10;

FIG. I1 is a side elevation view with portions broken away for clarity of presentation of a connecting switch section providing combined switching in accordance with the invention;

FIGS. llA-llE are sectional views taken as indicated from FIG. II;

FIG. 12 is a partial top view of the connecting switch section of FIG. 11;

FIG. 12A is a sectional view taken as indicated from FIG. l2;

FIG. 13 is an elevation view of a downline connecting switch section providing combined switching in accordance with the invention;

FIGS. l3A-13E are sectional views taken as indicated from FIG. 13;

FIG. 14 is a partial top view of the connecting switch section of FIG. 13;

FIGS. 14A and 14B are sectional views taken as indicated from FIG. 14;

FIG. 15 is an elevation view and illustrates an alternative rack assembled in accordance with the present invention;

FIG. 16 is a side elevation, with portions in section, and illustrates the alternative rack assembled in accordance with the invention;

FIG. 17 is a side elevation of an alternative embodiment of switch section assembled in accordance with the invention;

FIGS. 17A-17F are sectional views taken as indicated from FIG. 17; I

FIG. 18 is a partial top view of the connecting switch section of FIG. 17, and

FIGS. 18A and 18B are sectional views taken as indicated from FIG. 18.

DETAILED DESCRIPTION OF THE EMBODIMENT OF THE INVENTION FIG. 1 shows a prospective schematic illustration of the modes of switching that may be accomplished in accordance with the present invention. Switching is accomplished without the use of moving parts in the connecting guidebeam switch section. In accordance with the present invention when utilizing self-contained means carried on the rack to raise or lower the guide wheels, the rack may be switched horizintally from a main guidebeam to the left or to the right to diverging downline guidebeams, or may be continued through such connecting switch section on the mainline guidebeam. As is evidenced by the reverse arrows the switch section can be modified so that such horizontal switching may be accomplished into a through mainline guidebeam from guidebeams merging from the left or the right.

When utilizing a rack having both self-contained means for vertically moving the guide wheels in accordance with the present invention and having extendable and retractable support wheels, such as taught in our application Ser. No. 861,843 and adaptable with the present invention, the rack may be moved rapidly through a very complex interchange or a series of closely spaced-apart switch sections and switched vertically or horizontally or both in sequence without the need to reset the wheels after each portion of the switch section is passed. For example the guide wheels on a rack can be programmed to make the first possible right hand horizontal turn of FIG. 1. Then without resetting the guide wheels or support wheels the rack can be quickly switched through up to five of the next diverging horizontal guidebeams by proper prior programming or setting of the guide wheels and support wheels. In a similar manner vertical switching can proceed of follow horizontal switching by proper prior programming or setting of the support wheels and guide wheels as illustrated downline in FIG. 1. Utilizing both moving guidewheels and moving support wheels many combinations of switching are provided in accordance with the present invention. FIG. 1 is used to illustrate some of the modes of switching possible in accordance with the invention. 7

Refer now to FIGS. 2, 3, and 4. FIG. 2 is an elevation view of the preferred rack assembled in accordance with the present invention. FIG. 3 is a side elevation view of the preferred rack and FIG. 4 is a bottom view of the preferred rack of the present invention. The rack has a pair of horizontally spaced apart upper guide wheels 33 and 35 and a pair of horizontally spaced apart lower guidewheels 37 and 39. Each of the guidewheels is rotatably mounted on a normally vertically extending axle. Support wheels 38, 40, rotatably mounted on normally horizontal axles l8, 19 are used to move the rack along the running surfaces of the guidebeam. Power sources 85, 86 are connected to the support wheels to drive the wheels. The rack 20 in cludes a frame 22 which has overhanging arms 62, 63 which extend above the upper portion of the frame 22 to permit the upper guidewheels 33, 35 to engage the guidebeam l0 on the inner facing running surface 12 which forms the upper guidewheel running surface.

The upper guidewheels 33, 35 are movable in a direction normal to the direction of travel of the rack as indicated in phantom in FIGS. 2 and 3. The lower guidewheels 37, 39 are mounted on normally vertical axles 43, 45 of the frame 22. A pair of idler lower guidewheels 80, 81 are also mounted on normally vertical axles 83, 84 of the frame and are useful to budge gaps in the guidebeam switch sections as hereafter described. The lower guidewheels 37, 39 are also movable in a direction normal to the direction of travel of the rack as also shown in phantom in FIGS. 2 and 3. In order to select a desired path through a guidebeam switch section the upper-guidwheels 33, 35 and the lower guidewheels 37, 39 are moved in a complimentary fashion. Thus when the upper guidewheels 33, 35 are extended to the position shown in phantom, the lower guidewheels 37, 39 are retracted and moved closer to the frame as also indicated in phantom. The movement of the guidewheels in a direction normal to the direction of travel of the rack is preferably done when the rack is moving along the guidebeam to reduce friction caused by such vertical displacement of the guidewheels on the guidebeam running surfaces.

Self'contained means are thus provided on the rack for displacing the guidewheels in a direction normal to the direction of travel of the rack over a guidebeam. The movement is generally in a vertical direction with respect to the guidebeam. This transverse or vertical movement is done when it is desired to switch a rack from one guidebeam to another and realignment of the guidewheels is necessary to select the proper path through the switch section. In this aspect of the present invention the upper and lower guidewheels are moved up or down with respect to the rack. Appropriate linkage is used to extend or retract the axles of the guidewheels to thus move the guidewheels normal to the direction of movement of the rack and raise or lower the guidewheels with respect to the running surfaces of the guidebeam.

A hydraulic system may be used in conjunction with mechanical linkage to elevate and depress the guidewheels. For example a hydraulic cylinder 50 is connected to upper guidewheel 33 and lower guidewheel 37 by appropriate mechanical linkage. The master hydraulic cylinder 50 is also connected to upper guidewheels 35 and lower guidewheel 39 through a similar mechanical linkage. The operation of the hydraulic cylinder 50 is controlled by a suitable master control 51. Referring to the left-hand side of FIG. 2, a pushrod 52 extends from the hydraulic cylinder 50 and is connected to a pushrod extension 54 by means of a link pin 56. The pushrod extension 54' is connected to a pivotally mounted bell crank 58 by means of a pin 60. The bell crank 58 is pivotally mounted on the frame 22 by a pin 62. The other arm of the bell crank 58 is pivotally connected to a pair of pushrods 64 and 66 by means of pins 76 and 72. When the bell crank 58 is pivoted about pin 62 and rod 68 and rod 66 are pushed or pulled de-' pending on the direction of movement 'of the bell crank. This up or down movement is transmitted to the guidewheels 33, 37 by suitable linkage. Thus the axles 43 of lower guidewheel 37 is rotatably and reciprocally mounted in bearing 42 and a universal joint 47 is used to connect rod 66 with the end of axle 43. Wheel 37 is moved between the positions indicated in FIG. 2 by movement of the above described linkage when the master cylinder is activated.

The upper guidewheel 33 is extended or retracted in complimentary relationship to the lower guidewheel by extending or retracting axle 41. The axle 41 is rotatably and reciprocally mounted in a bearing and rotatably carried in a movable bearing assembly 79. This bearing assembly 79 is moved up or down by suitable gear teeth acted on by torque arm 78. The torque arm 78 to rotated by means of lever arm 76 being pivoted by rod 68 which is connected to the arm 76 by a pin 77.

The other guide wheels 35, 39 are moved in complimentary fashion by linkage extending from the other side of the master cylinder 50. Note that the bell crank 258 is mounted in reversed fashion compared to bell crank 58 so that themovement of all the guidewheels is complimentary. That is to say when the upper guide wheels 33, 35 move up or away from the frame 22 then the lower guide wheels 37, 39 also move up or in this instance toward the frame 22. In the right-hand side of I FIG. 2, a suitable pushrod 252 extends from the hy-' draulic cylinder 50 and is connected to pushrod extension 254 by means of a link pin 256. The pushrod extension 254 is connected to a pivotally mounted bell crank 258 by means of pin 260. The bell crank 258 is pivotally mounted on the frame by a pin 262. The other arm of the bell crank 258 is pivotally connected to a pair of pushrods 264 and 266 by means of pin 270 and 272. When the bell crank 258 is pivoted about pin 262 rod 268 and rod 266 are pushed or pulled depending on the direction of movement of the bell crank. This up or down movement is transmitted to the guidewheels 35, 39 by suitable linkage. Thus the axles 45 of lower guidewheel 37 is rotatably and reciprocally mounted in bearing 242 and a universal joint 247 is used to connect rod 266 with the end of the axle 45. Wheel 39 is moved between the positions indicated in FIG. 2 by the movement of the above described linkage when the master cylinder is activated. The upper guidewheel 35 is extended or retracted in complimentary relationship to the lower guidewheel by extending or retracting a suitable axle. The axle is rotatably amd reciprocally mounted similarly to axle 41 in a bearing and rotatably carried in movable bearing assembly. This bearing assembly is also moved up or down by suitable gear teeth acted on by torque arm 278. The torque arm 278 to rotated by means of lever arm 276 being pivoted by rod 268 which is connected to the arm 276 by pin 277.

FIG. 3 also illustrates a further aspect of the present invention in that the embodiments described herein may also be provided with an extendable and retractable support wheel for cooperation with a ramped guidebeam switch section as described and claimed in our copending application Ser. No. 861,843. Thus support wheel 40 may be moved to the positions indicated in phantoms as 40 and 40". When both the movable support wheels and the movable guidewheels are used cooperatively in accordance with the invention a large number of rapid switch possibilities are obtained.

In an alternative embodiment of the invention the guide wheels of a rack are moved normal or transverse to the direction of travel of the rack by elevating or lowering the entire frame of the rack bychanging the position of the support wheel with respect to the frame. This is done by self-contained means carried on the frame. This embodiment is indicated in FIGS. 5, 6, 7, and 8. FIG. 5 is an elevation view of this alternative embodiment of apparatus assembled in accordance with the present invention. FIG. 6 is a side view of the apparatus of the invention shown in FIG. 5 with the guidewheels in the down position while FIG. 7 is a side elevation view of the apparatus of the invention with the guidewheels in the up position. FIG. 8 is a bottom view of the alternative apparatus shown in FIG. 5.

A rack, generally indicated by the number 120, is formed by means of various components attached to aframe 122. The frame has a series of spaced apart wheels rotatably attached thereto. The wheels include upper guidewheels 133 and 135 and lower dual spaced apart guidewheels 137, 139, 141 and 143. The support wheels which are also rotatably mounted on the frame are indicated as 145 and 147. In accordance with the 9nvention the guidewheels 133, 135, 137, 139, 141, 143 are caused to move in a direction normal or transverse to the direction of travel of the rack by selfcontained means carried on the rack. In the alternative embodiment ofthe invention such movement is accomplished by raising or lowering the entire rack by changing the position of the support wheels 145, 147 to two or more different elevations as indicated in phantom in FIG. 5. Thus in this embodiment of the invention the support wheels are mounted in housings 151 and 153. The wheels and 153 are driven by motors 130 and 131. The housings 151 and 153 are pivotally mounted on frame 122 by pins 155 and 157. By applying force to the housings they may be pivoted between the two positions indicated. A hydraulic cylinder 123 is used to activate a mechanical linkage to move the housings of the support wheels 145, 147 to at least these two different positions. As indicated in FIGS. 6 and 7 the frame, including the guidewheels, can be transversely moved up or down on the guidebeam by lifting or lower the frame 122 with respect to the support wheels 145, 147.

The hydraulic cylinder 123 has at least two positions. The rod extension 124 of the hydraulic cylinder is connected to a pivotally mounted crank 125 by a pin 126. The vrank 125 pivots about a pin 127 which is connected to the frame 122. An elongated arm 129 is pivotally connected to the lower end of the crank 125 by pin 128 and extends to a couble acting lever 101 and is connected thereto by pin 103. The double acting lever 101 is connected to the frame 122 by pin 102 and to the support wheel housing 151 by pin 105. Thus as arm 129 is pushed or pulled the housing 151 is moved as indicated in phantom. The other housing 153 ismoved in concert with housing 151 by an elongated arm which is connected to double acting lever 106 by pin 107. This lever 106 is connected to the frame 122 by pin 103 and to the housing 153 by pin l09.-

When the frame is moved up or down by the action of the support wheels the guidewheels are also moved in a direction normal or transverse to the direction of movement of the rack on the guidebeam. This transverse movement of the guidewheels is useful in switching as described below.

FIGS. 9 through 14 illustrate connecting guidebeam switch sections assembled in accordance with the preferred embodiment of the present invention for cooperation with the above described racks to permit switching of the racks of the present invention. The connecting switch sections afford switching in a horizontal manner. Vertical switching may also be done as described in our co-pending US. application Ser. No. 861,843. The racks of the present invention are cantilevered on a guidebeam by means of guidewheels and support wheels. Switching is accomplished in a guidebeam switch section by programming the guidewheels by moving them traverse to the longitudinal center line of the guidebeam so that the rack will travel a predetermined path through the switch section.

The racks as discussed above are the types having a support wheel disposed well below the center of gravity of the rack. The horizontal mode of switching refers to the overall disposition of the rack through the connecting switch section. Thus when referring to a horizontal switch section it is understood that there may be if desired vertical displacement of the rack immediately downline of the horizontal switch to provide for a vertical movement to a downline guidebeam. It is evident that while the switch sections are described as proceeding from an upline guidebeam to one of two more downline guidebeams, the opposite also can be true. That is, by reversing the direction of travel and the sequencing of displacing the guidewheels or support wheels and by reversing the elements of the connecting switch section the rack by come from one of two spaced apart upline guidebeams through a connecting switch section to merge into a single downline guidebeam.

A horizontal switch for switching the racks of the present invention is illustrated in FIG. 9, FIGS. 9A to 9E, FIG. 10 and FIGS. 10A and 108. A mainline guidebeam is generally indicated by the number 160. Two substantially horizontally spaced apart guidebeams, 161 and 162, are shown downline from the upline guidebeam 160. A connecting switch section which provides for selectively directing a rack from upline guidebeam to either of the two downline guidebeams, 161 or 162, is located between the upline guidebeam and the downline guidebeams. The switch portions are illustrated in section in FIGS. 9A-9E and FIG. 10A. The wheels of the rack, as they move into the connecting switch section, select the path through which they will proceed. There are no moving parts in the guidebeam switch section itself. Thus the guidewheels of the rack by their position on the guide running surface of the guidebeam switch section select the path on which the rack will travel through the connecting switch section. By virtue of making such a selection, the rack is directed to either of the desired downline guidebeams. As described above the self-contained means of the rack moved both the upper'and lower guide wheels in complementary fashion in a vertical manner to select the desired guide wheel running surface. This vertical movement is at a right angle or normal to the direction of travel of the rack and moved the guide wheels transversely on the guidebeam with respect to the longitudinal centerline of the guidebeam.

The movement of the rack through the horizontal switch section, illustrated in FIGS. 9, 9A to 9E and FIGS. 10, A and 108, will now be described in detail. The path of the rack through the switch section will be described in moving the rack from upline guidebeam 160 to downline guidebeam 162. Assume first that it is desired to move the rack from upline guidebeam 160 to downline guidebeam 161. The guidewheels of the rack are programmed as herein before described to follow the appropriate guidewheel running surfaces. Thus referring to FIG. 9 it is seen that the guidewheels of the rack in normal running position will be moving over upper guide running surface 169 and lower guide running surface 167. The support wheel travels on support wheel running surface 165. Since it is desired to move the rack from upline guidebeam 160 through the connecting switch section to downline guidebeam 161 is substantially a horizontal mode, the guidewheels of the rack are maintained in position to follow the lower portion 170 of upper guide running surface 169 which develops between sections 9C and 9D. In this regard upper guide running surface may be wide enough so that two surfaces 170 and 173 may develope. The lower guidewheels follow the lower portion of surface 167 through the connecting switch section. In this manner the rack is transferred to the guidebeam 161 as illustrated in FIG. 9E and FIGS. 10A and 108. Thus by simply maintaining the guide wheels of the rack in the down or lower position the rack is directed to the selected downline guidebeam 161. If the guide wheels were in the up position as the rack approached the switch and it was desired to switch to guidebeam 161, the self-contained means would be activated to move the guidewheels vertically down the guidebeam prior to reaching the switch section.

If it is desired to direct the rack from upline guidebeam 160 to downline guidebeam 162, both the upper and lower guidewheels are elevated on their respective running surfaces of the guidebeam so that the upper guide wheels will contact upper portion 173 of the guide running surface which develops from guide running surface 169 between FIGS. 9C and 9D. The lower guide wheels will then clear surface 167. A second lower guide running surface 168 is developed between FIGS. 9A and 9B and this surface is used by the upper ofthe lower dual guide wheels. This upper wheel of the dual lower guide wheels is the idler wheel 80, 82 of FIG. 3 and 141, 143 of FIG. 5. As standard running surface as shown in FIG. 9A and FIG. 10B is developed downline of the section shown in FIG. 9E and the rack is returned to the normal running on the guidebeam with the guidewheels left in position or changed as desired.

A combined switch for switching the racks of the present invention is illustrated in FIG. 11, FIGS. llA-IIE, FIG. 12, FIG. 12A, FIG. 13, FIGS. l3A1eE, FIG. 14 and FIGS. 14A and 148. The bombined switch utilizes both extendable and retractable support wheels and vertically movable guidewheels to provide for passing the rack through numerous closely spaced switches without having to rapidly reset either the support wheels or the guidewheels. Thus the switch section illustrated in FIGS. 11 and 12 utilizes a ramped support wheel running surface to switch or pass through a rack. Downline of this switch section as illustrated in FIGS. 13 and 14 a guidewheel switch section is connected and utilizes vertically movable guidewheels to switch the rack. In this manner a rack which passes straight through theswitch section of FIGS. 11 and 12 can be further switched in the FIGS. 13 and 14 switch by a predetermined setting of the guidewheels prior to entering the support wheel switch section without moving the support wheels after entering-the support wheel section.

The switch section of FIGS. 11 and 12 will be first described in detail. A mainline guidebeam is generally indicated by the number 180. Two substantially horizontally spaced apart guidebeams, 181 and 182, are shown downline of the upline guidebeam 180. A connecting switch guidebeam section which provides for selectively directing a rack from upline guidebeam to either one of the two downline guidebeams. 181 or 182, is located between the upline and downline guidebeams. The switch portion is illustrated in FIGS. 11A-11E. The predetermined wheels of the rack, as they move into the connecting switch section, select the path through which the rack will proceed. Thus the extendable and retractable support wheels of the rack select the path on which it will run through the first portion of the combined connecting switch section. By virtue of making such a selection, the rack is directed to either of the desired downline guidebeams.

The operation of the rack through the horizontal switch section illustrated in FIGS. 11 and 12 will now be described in detail. The path of the rack through the switch section will be described in moving the rack from upline guidebeam 180 to both downline guidebeams 181 and 182.

Assume for the purposes of description that it is desired to desire a rack from upline guidebeam 180 to downline guidebeam 181. The support wheels of the rack are programmed to follow the appropriate support wheel running surface. Thus referring to FIG. 11A it is seen that a support wheel of the rack in normal running position is moving over support wheel running surface 185. The support wheel is in retracted position with respect to the rack. An upper guide running surface 189 is provided for the upper guide wheels. A lower guide running surface 187 is provided for the lower guide wheels and a support running surface 185 is provided for the support wheels. Since it is desired to move the rack from upline guidebeam 180 through the connecting switch section to downline guidebeam 181 in sub stantially a horizontal mode the support wheel of the rack is maintained in a normal retracted position so as to ride on the normal portion of the horizontal support running surface 185.

As the rack proceeds downline through the connecting section to a position illustrated in FIG. 118 the support wheel running surface 185 ramps down. The lower guidewheels continue to run on surface 187 while the upper guidewheels continue to run on surface 189 to hold the rack in cantilevered position on the guidebeam. The support wheel running surface 185 has lowered to the required extent as illustrated in FIG. 11C. Again the rack continues to move in cantilevered fash- 1 from the guidebeam 182 and is cantilevered on surfaces 189, 185 and 187. The sectional view FIG. 12A illustrates the running surfaces of the downline guidebeam 181 as the guidebeam returns to its normal form.

When it is desired to move a rack from upline guidebeam 180 to the other downline guidebeam 182 the support wheel of the rack is extended as the rack moves into the portion of the connecting switch section illustrated in FIG. 11A. The support wheel is moved so that it can run on running surface 190 as shown in FIG. 118 while the upper guide wheels move on surface 189. It is of course within the scope of the invention to have a running surface 191) be two running surfaces thus allowing 3 directional switching without altering the support wheels in the switch section a new surface 188 is developed for the so-called idler wheel which is the upper of the lower dual guidewheels. In FIG. 11C the lower guide runnign surface 187 ramps down and the lower of the dual lower guide wheels begins to come off of surface 187 since the support wheel is now running on the support running surface 190. Running surface 188 is available for the idler wheel of the lower guide wheels through all portions of the switch from before FIG. 118 to after FIG. 11E. The lower guide running surface 187 has dropped down far enough to free the lower guide wheels by FIG. 11C when the support wheel is on surface 190. Between FIG. 11C and FIG. 11E the running surfaces leading to downline guidebeams 181 and 182 diverge. In FIG. 11E the upper guide wheels are located on surface 193 which has smoothly developed and diverged from surface 189. The lower of the dual lower guide wheels are above surface 187 and therefor free to move in over surfaces 187 and 185 without touching them. Thus a window or gap for passing the rack through guidebeam 181 onto guidebeam 182 matures between FIG. 11C and FIG.

HE. A rack located at FIG. 11E and having its support wheel on surface 190 would have the upper guide wheels on surface 193 and its lower idler wheel on surface 188. The body portion of the rack clears both the upper and lower portions of guidebeam 181 and the rack may now pass through the guidebeam 182 which returns to standard mainline configuration.

After passing on to a downline guidebeam it may be desirable to immediately incorporate another switch section into the system. Thus the switch section illustrated in FIGS. 13 and 14 embodiment may be connected to guidebeam 182 immediately downline and switching done by vertical guidewheel setting without the need of rapidly moving the support wheel. This is the combined mode of switching in accordance with the present invention. Thus by proper guidewheel setting the rack can be switched to guidebeam 182 of FIG. 13 to downline guidebeam 361 or 362.

The mainline guidebeam is generally indicated by the number 182. Two substantially horizontally spaced apart guidebeams. 361 and 362, are shown downline from the upline guidebeam 182. A connecting switch section which provides for selectively directing a rack from upline guidebeam 182 to either of the two downline guidebeams, 361 or 362, is located between the upline guidebeam and the downline guidebeams. The switch portions are illustrated in section in FIGS. 13B 13E and FIG. 14A. The wheels of the rack, as they move into the connecting switch section, select the path through which the rack will proceed. There are no moving parts in the guidebeam switch section itself and it is not necessary to reposition the support wheels. Thus the guidewheels of the rack by their position on the guide running surface of the guidebeam switch section select the path on which the rack will run through the connecting section. By virtue of making such a selection, the rack is directed to either of the desired downline guidebeams. As described above the selfcontainer means of the rack moves both the upper guide wheel and the lower of the dual lower guide wheels in complementary fashion in a vertical manner on the guidebeam to select the desired guide wheel running surface. This vertical movement is at a right angle or normal to the direction of travel of the rack along the longitudinal centerline of the guidebeam.

The movement of the rack through the horizontal switch section, illustrated in FIG. 13, FIGS. 13A13E, FIG. 14, and FIGS. 14A and 148, will now be described in detail. The path of the rack through the switch section will be described in moving the rack from upline guidebeam 182 to downline guidebeam 361 and from upline guidebeam 182 to downline guidebeam 362. Assume first that it is desired to move the rack from upline guidebeam 182 to downline guidebeam 361. The guidewheels of the rack are programmed as herein before described to follow the appropriate guidewheel running surfaces. Thus referring to FIG. 1e it is seen that the guidewheels of the rack will be moving over the lower portion 369 of the upper guide running surface and lower guide running surface 367. The support wheel travels on support wheel running surface 365. Since it is desired to move the rack from upline guidebeam 182 through the connecting switch section to downline guidebeam 361 in substantially a horizontal mode, the guidewheels of the rack are maintained in position to follow the lower portion 369- of upper guide running surface which diverges between sections 13C and 13D. The lower guidewheels follow surface 367 through the connecting switch section. In this manner the rack is transferred to the guidebeam 361 as illustrated in FIG. 13E and FIGS. 14A and 14B. Thus by simply maintaining the guide wheels of the rack in the down or lower position the rack is directed to the selected downline guidebeam 361.

If it is desired to direct the rack from upline guidebeam 182 to downline guidebeam 362, both the upper guide wheels and the lower of the dual lower guidewheels are elevated on their respective running sur faces of the guidebeam so that the upper guide wheels will contact the upper portion 373 of the upper guide running surface which diverging between FIGS. 13C and 13D and, being elevated, the lower guide wheels will clear surface 367. A second lower guide or idler running surface 368 is developed between FIGS. 13A and 13B and this surface is used by the idler or upper of the lower dual guide wheels. This upper wheel of the dual lower guide wheels is the idler wheel 80, 82 of FIG. 3 and 141, 143 of FIG. 5. A standard running surface shown in FIG. 13A and FIG. 14B is developed downline of the section shown in FIG. 13E and the rack is returned to the normal running on the guidebeam with the guidewheels and support wheels left in position or changed as desired. An alternative embodiment of apparatus of the present invention incorporates a support wheel at the top of the rack. Vertically movable guide wheels and if desired extendable and retractable support wheels are used to switch from a mainline guidebeam section either to the left or to the right in a horizontal fashion to a diverging downline guidebeam and to switch from the mainline guidebeam section vertically either up or down to a diverging downline guidebeam. Also the opposite course may be followed by a rack through such a switch section (or obviously a mirror image switch section) constructed to provide for merging from two downline guidebeams into a main upline guidebeam. In either a merging or diverging mode switching is accomplished by the rack without the use of moving parts in the connecting guidebeam switch section. Vertically movable guide wheels on the rack and also if desirable extendable and retractable support wheels of the rack, provide for selecting one of two or more paths on a guidebeam switch section to thus determine the course that the rack will take through the connecting switch section.

In FIG. 15 and FIG. 16 the alternative embodiment of apparatus assembled in accordance with the present invention is shown in schematic form. FIG. 15 is a side elevation and FIG. 16 is an end elevation, partially in section, showing an alternative rack generally indicated by the number 220 attached to and in running position on an alternative elongated guidebeam which is generally indicated by the number 230. The guidebeam is formed to provide a path in the transportation system and serves tp carry the running surfaces on which the rack 220 moves. The rack 220 includes a frame member 222 having a number of sets of spaced apart wheels rotatably attached thereto. The sets of wheels include the upper guide wheels 233 and 333; the lower guide wheels 239 and 339; the support wheels 238 and 338 and the auxiliary support wheels 240 and 340. The support wheels 238 and 338 as will hereinafter be discussed in detail are usually driven by a power source and therefore also function as drive wheels to move the rack along the guidebeam. The alternative embodiment rack has spaced apart upper guide wheels 233 and 333 and lower guide wheels 239 and 339. The guide wheels are positioned on the frame at suitable intervals depending on the load and the length of the rack. It is usually desirable to have at least two upper guide wheels and two lower guide wheels and two support wheels for each rack. Dual upper auxiliary support wheels 240 and 340 are also provided for each support wheel in order that certain switching operations may be accomplished by this alternative rack.

As in the preferred embodiment of apparatus, the alternative guidebeam 230 is held in desired position by suitable support means such as for example by a series of columns such as column 244, spaced apart along the right of way. The guidebeam 230 may be composed, for example, of prestressed concrete sections resting end to end on a series of supports such as column 244. Suitable overall dimensions for such prestressed sections as a guide to understanding the present invention have been found to be about 8 feet high by 6 feet wide and 11 feet long.

The guidebeam 230 provides at least three spaced apart running surfaces for the rack. Thus on each mainline right of way portion of the alternative guidebeam there is provided an upper guide running surface 234, a lower guide running surface 231 and a support wheel running surface 242. The upper guide running surface 234 and the lower guide running surface 231 have sub stantially vertically disposed running surfaces to accommodate the upper and lower guide wheels respectively. The support wheel running surface 242 is in a substantially horizontal plane to accommodate the support wheels. As illustrated in FIG. 15 and FIG. 16, the self-powered rack 220 is adapted to be held and to be moved on the three running surfaces of the guidebeam 238 in cantilever fashion. Thus the upper guide surface 234 is formed on a vertical inward facing wall of the guidebeam 230 while the lower guide running surface 231 is formed on a vertical outward facing wall of the guidebeam 230. The upper guide wheels 233, 333 and the lower guide wheels 239, 339 cooperate with the support wheels 238, 338 to position the rack in cantilever fashion on the guidebeam 230..

The rack 220 is driven along the guidebeam 230 by means of a suitable power source supplying power to the support wheels. As noted, it is preferred in the alternative embodiment of apparatus to use a wheel which rotates on a horizontal axis as a dirve wheel. It is of course possible to provide either or both the upper and lower guide wheels with power. Motive power is supplied to the support wheel 238 by a suitable power source. Such a power source may for example be an electric motor or an internal combustion engine. Such a suitable power source is schematically illustrated in FIG. 15 by the box indicated by the number 248. If it is desired to drive more than one support wheel, then a second power source 246 may be utilized to drivewheel 338. Suitable drive train means are provided to connect power source 246, 248 to the support wheels 238, 338. Control means 250 are preferably carried on the rack 220 to control the power sources 246 and 248 and the movement of the wheels and thus the rack 220 along the guidebeam 230. Control means 250 is preferably electrically activated and in many instances will be tied into a computer network so that a number of racks may be moved at closely spaced intervals along the guidebeam system.

This alternative form of the present invention provides for switching a rack 220 having a top support wheel from a mainline upline guidebeam to one of two or more diverging downline guidebeams in ahorizontal mode and also to be merged from two upline guidebeams to a single downline guidebeam in a horizontal mode. The vertically movable wheel configuration of the upper and lower guide wheels permit continuous contact of the respective upper and lower guide wheels to selected surfaces during the entire switching operation as the rack is switching from one guidebeam to another through the switch section. In accordance with the present invention self-contained means carried on the rack are utilized to raise or lower the guide wheels. The rack may be switched horizontally from a main guidebeam to the left or to the right to diverting downline guidebeams, or may be contained through such connecting switch section on the mainline guidebeam.

The switch section can be modified so that such horizontal switching may be accomplished into a through mainline guidebeam from guidebeams merging from the left or the right. When utilizing a rack having both self-contained means for vertically moving the guide wheels as disclosed above in detail in the description of the preferred embodiment of the present invention and having extendable and retractable support wheels, and dual vertically spaced apart upper and lower guidewheels, such as taught in our application Ser. No. 861 ,843 and adaptable for use with the present invention, the alternative upper support wheel rack may be moved rapidly through a very complex interchange or a series of closely spaced-apart switch sections and switched vertically or horizontally or both in sequence without the need to reset the wheels after each portion of the switch section is passed. For example the guide wheels on a rack can be programmed to make the first possible right hand horizontal turn of FIG. 1. Then without resetting the guide wheels or support wheels the rack can be quickly switched through up to five of the next diverging horizontal guidebeams by proper prior programming or setting of the guide wheels and support wheels. In an similar manner vertical switching can proceed or follow horizontal switching by proper prior programming or setting of the support wheels and guide wheels as illustrated downline in FIG. 1. Utilizing both moving guidewheels and moving support wheels many combinations of switching are provided in accordance with the present invention. FIG. Iis used to illustrate some of the modes of switching possible in accordance with the invention.

The guidewheels and the support wheels of this alternative embodiment of apparatus are moved in their respective modes as fully discussed and illustrated in the detailed description of the present invention. Therefore a repeated detailed description of such structure will not be necessary. Thus self-contained means are provided on the rack for displacing the guidewheels in a direction of travel of the rack over a guidebeam. The movement is generally in a vertical direction with respect to the longitudinal centerline of the guidebeam. .This transverse or vertical movement is done when it is desired to switch a rack from one guidebeam to another and realignment of the guidewheels is necessary to select the proper path through the switch section. In one aspect of the present invention the upper and lower guidewheels are moved up or down with respect to the rack. Appropriate linkage is used to extend or retract the axles of the guidewheels to thus move the guidewheels normal to the direction of movement ofthe rack and raise or lower the guidewheels with respect to the running surface of the guidebeam. In an other aspect of the invention the guidewheels of a rack are moved normal or transverse to the direction of travel of the rack by elevating or lowering the entireframe of the rack by changing the position of the support wheel with respect to the frame.

A horizontal switch for this alternative embodiment of apparatus is illustrated in FIG. 17, FIGS. 17A-l7F, FIG. 18 and FIGS. 18A and 188. In this switch a rack may be directed from upline guidebeam 410 to either of a pair of diverging downline guidebeams 412 and 414. If it is desired for example to direct a rack from guidebeam 410 to guidebeam 414 the following running surfaces would be utilized. A support running surface 420 is used as the mainline support running surface. Guide wheel running surfaces 430 and 431 are provided for the upper guide wheels and a guide wheel running surface 424 is provided for the lower guide wheels. When it is desired to go to guidebeam 414 the guidewheels are moved up if they are not already in such position. An upper guide running surface 431 begins to diverge between FIGS. 21D and 21E. This serves to carry the upper wheel of the dual upper guide wheels on running surface 431 through the switch section to guidebeam 414. The lower guide wheels run on surface 424 through the entire connecting switch section above surface 436 to guidebeam 414. The support wheel follows surface 420.

When it is desired to switch the rack from guidebeam 410 to guidebeam 412 the guidewheels are moved vertically down or maintained in such position if already there. The upper guide wheels follow surface 430 and the lower guide wheels follow surface 436. A new auxiliary horizontal running surface 432 developes between FIGS. 17A and 17B and the dual upper auxiliary support wheels 240 and 340 run on this surface through the portion of the window section of the switch when the main support wheels come off surface 420. The

auxiliary support wheels, of course, may be powered or momentum may be used to carry the rack through this portion of the switch. The upper guide wheels operate on surface 430 through the connecting switch section while the lower guide wheels pick up surface 436 in FIG. 21D and utilize this surface through the window section of the switch. The rack is thus switched to guidebeam 412.

Although specific embodiments of the present invention have been described in detail the invention is not to be limited to any such specific embodiments but is meant to include all embodiments coming within the scope of the appealed claim.

We claim:

1. Apparatus for use in cantilever fashion on a guidebeam having an inwardly facing vertical upper guide running surface, an outwardly facing vertical lower guide running surface and a substantially horizintal support running surface comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the inwardly facing vertical upper guide running surface, at least two horizontally spaced apart lower guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the outwardly facing vertical lower guide running surface, at least a pair of horizontally spaced apart support wheels rotatably mounted on normally horizontal axles of said frame and adapted to move on the support running surface and self-contained means carried on said frame for moving said upper and lower guide wheels transversely on said guidebeam between at least two vertically spaced apart positions on the vertical running surfaces of the guidebeam.

2. Apparatus for use in cantilever fashion on a guidebeam' having an inwardly facing vertical upper guide running surface, an outwardly facing vertical lower guide running surface and a substantially horizontal support running surface comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the inwardly facing vertical upper guide running surface, at least two horizontally spaced apart lower guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the outwardly facing vertical lower guide running surface, at least a pair of horizontally spaced apart support wheels rotatably mounted on normally horizontal axles of said frame and adapted to move on the support running surface, said pair of horizontal axles for said support wheels being located between said upper and lower guide wheels, self-contained means carried on said frame for moving said upper and lower guide wheels transversely on said guidebeam between at least two vertically spaced apart positions on the vertical running surfaces of the guidebeam and motive means for moving said frame along a guidebeam.

3. The apparatus of claim 2 further characterized by means carried by said rack for extending and retracting said support wheels in a direction normal to the direction of travel of said rack on said guidebeam.

4. The apparatus of claim 2 further characterized in that said self-contained means carried on said frame for moving said upper and lower guidewheels are means for extending and retracting the axles of said guidewheels in a direction normal to the direction of travel of the rack.

5. The apparatus of claim 2 further characterized in that said self-contained means carried on said frame for transversely moving said guidewheels are vertically movable support wheels relative to the guide wheels of said rack.

6. The apparatus of claim 5 further characterized in that the support wheels are mounted in housings and that said housings are pivotally mounted to said frame and that means are provided to pivot said housings with respect to said frame to raise or lower the guidewheels with respect to the support wheels.

7. Apparatus for use in cantilever fashion on a guidebeam comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably and reciprocably spaced apart upper guide wheels rotatably and reciprocally mounted on normally vertical axles of said frame, at least two horizontally spaced apart lower guide wheels rotatably and reciprocably mounted on normally vertical axles of said frame, at least a pair of horizontally spaced apart support wheels having axles located between said upper guidewheels and said lower guidewheels, means for reciprocating said upper guidewheels and said lower guidewheels while said wheels are rotating and means for moving said frame along a guidebeam.

8. Apparatus of claim 7 further characterized in that sets of said upper guide wheels and said lower guide wheels are linked together for reciprocation.

9. Apparatus for use in cantilever fashion on a guidebeam comprising a frame, at least two horizontally spaced apart upper guidewheels rotatably mounted on normally vertical axles of said frame, at least two horizontally spaced apart lower guidewheels rotatably mounted on normally vertical axles of said frame, a pair of housings pivotally mounted on said frame, a support wheel rotatably mounted on normally horizontal axles contained in each of said pair of housings and located between said upper and lower guidewheels, means for pivoting said housings to thereby raise or lower said guidewheels with respect to said support wheels and means for moving said frame longitudinally along a guidebeam.

10. A method of switching a cantilevered rack between a main guidebeam and one of two or more diverging guidebeams comprising simultaniously contacting an inwardly facing vertical upper guide running sur face of a guidebeam with an upper guide wheel of a rack, an outwardly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam with a support wheel of said rack to maintain said rack in cantilevered position on said guidebeam, selecting running surfaces to a downline guidebeam to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to moveover said selected running surfaces to said downline guidebeam.

11. A method of switching a cantilevered rack between a main guidebeam and one of two or more diverging guidebeams comprising simultaniously contacting an inwardly facing vertical upper guide running surface of a guidebeam with an upper guide wheel of a rack, an outwardly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam witha support wheel of said rack, selecting running surfaces to one of two or more downline guidebeams to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to move over said selected running surfaces to said one of said two or more downline guidebeams.

12. A method of switching a cantilevered rack to a downline guidebeam from one of two or more upline guidebeams comprising simultaneously contacting an inwardly facing vertical upper guide running surface of an upline guidebeam with an upper guide wheel of a rack, an outwardly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam with a support wheel of said rack to maintain said rack in cantilevered position on said guidebeam, selecting running surfaces to a downline guidebeam to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to move over said selected running surfaces to said downline guide- 

1. Apparatus for use in cantilever fashion on a guidebeam having an inwardly facing vertical upper guide running surface, an outwardly facing vertical lower guide running surface and a substantially horizintal support running surface comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the inwardly facing vertical upper guide running surface, at least two horizontally spaced apart lower guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the outwardly facing vertical lower guide running surface, at least a pair of horizontally spaced apart support wheels rotatably mounted on normally horizontal axles of said frame and adapted to move on the support running surface and self-contained means carried on said frame for moving said upper and lower guide wheels transversely on said guidebeam between at least two vertically spaced apart positions on the vertical running surfaces of the guidebeam.
 2. Apparatus for use in cantilever fashIon on a guidebeam having an inwardly facing vertical upper guide running surface, an outwardly facing vertical lower guide running surface and a substantially horizontal support running surface comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the inwardly facing vertical upper guide running surface, at least two horizontally spaced apart lower guide wheels rotatably mounted on normally vertical axles of said frame and adapted to move on the outwardly facing vertical lower guide running surface, at least a pair of horizontally spaced apart support wheels rotatably mounted on normally horizontal axles of said frame and adapted to move on the support running surface, said pair of horizontal axles for said support wheels being located between said upper and lower guide wheels, self-contained means carried on said frame for moving said upper and lower guide wheels transversely on said guidebeam between at least two vertically spaced apart positions on the vertical running surfaces of the guidebeam and motive means for moving said frame along a guidebeam.
 3. The apparatus of claim 2 further characterized by means carried by said rack for extending and retracting said support wheels in a direction normal to the direction of travel of said rack on said guidebeam.
 4. The apparatus of claim 2 further characterized in that said self-contained means carried on said frame for moving said upper and lower guidewheels are means for extending and retracting the axles of said guidewheels in a direction normal to the direction of travel of the rack.
 5. The apparatus of claim 2 further characterized in that said self-contained means carried on said frame for transversely moving said guidewheels are vertically movable support wheels relative to the guide wheels of said rack.
 6. The apparatus of claim 5 further characterized in that the support wheels are mounted in housings and that said housings are pivotally mounted to said frame and that means are provided to pivot said housings with respect to said frame to raise or lower the guidewheels with respect to the support wheels.
 7. Apparatus for use in cantilever fashion on a guidebeam comprising a frame, at least two horizontally spaced apart upper guide wheels rotatably and reciprocably spaced apart upper guide wheels rotatably and reciprocally mounted on normally vertical axles of said frame, at least two horizontally spaced apart lower guide wheels rotatably and reciprocably mounted on normally vertical axles of said frame, at least a pair of horizontally spaced apart support wheels having axles located between said upper guidewheels and said lower guidewheels, means for reciprocating said upper guidewheels and said lower guidewheels while said wheels are rotating and means for moving said frame along a guidebeam.
 8. Apparatus of claim 7 further characterized in that sets of said upper guide wheels and said lower guide wheels are linked together for reciprocation.
 9. Apparatus for use in cantilever fashion on a guidebeam comprising a frame, at least two horizontally spaced apart upper guidewheels rotatably mounted on normally vertical axles of said frame, at least two horizontally spaced apart lower guidewheels rotatably mounted on normally vertical axles of said frame, a pair of housings pivotally mounted on said frame, a support wheel rotatably mounted on normally horizontal axles contained in each of said pair of housings and located between said upper and lower guidewheels, means for pivoting said housings to thereby raise or lower said guidewheels with respect to said support wheels and means for moving said frame longitudinally along a guidebeam.
 10. A method of switching a cantilevered rack between a main guidebeam and one of two or more diverging guidebeams comprising simultaniously contacting an inwardly facing vertical upper guide running surface of a guidebeam with an upper guide wheel of a rack, an outwarDly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam with a support wheel of said rack to maintain said rack in cantilevered position on said guidebeam, selecting running surfaces to a downline guidebeam to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to move over said selected running surfaces to said downline guidebeam.
 11. A method of switching a cantilevered rack between a main guidebeam and one of two or more diverging guidebeams comprising simultaniously contacting an inwardly facing vertical upper guide running surface of a guidebeam with an upper guide wheel of a rack, an outwardly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam with a support wheel of said rack, selecting running surfaces to one of two or more downline guidebeams to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to move over said selected running surfaces to said one of said two or more downline guidebeams.
 12. A method of switching a cantilevered rack to a downline guidebeam from one of two or more upline guidebeams comprising simultaneously contacting an inwardly facing vertical upper guide running surface of an upline guidebeam with an upper guide wheel of a rack, an outwardly facing vertical lower guide running surface of said guidebeam with a lower guidewheel of said rack and a horizontal support running surface of said guidebeam with a support wheel of said rack to maintain said rack in cantilevered position on said guidebeam, selecting running surfaces to a downline guidebeam to which to move said rack, cooperatively moving said guidewheels of said rack in a direction normal to the direction of travel of said rack to move said guidewheels and said support wheel to said selected running surfaces and causing said rack to move over said selected running surfaces to said downline guidebeam. 